Waveform Generator

[eth0]

Hi all,
Just wondering what you guys thought to the idea of a waveform generator chip?

I'm aware that there is a "pulser" that i'm told generates a short-edge square wave, but i was wondering if there was merit in producing a chip that could allow the user to pick the waveform e.g Sine,Square, Triangle, Sawtooth etc, it's frequency and value range.

[Jok]

Basically, the sine would...be a sine output. 0 to 1, a square would have 2 outputs, 0 to 1 and 1 to 0, triangle...3 outputs, Sawtooth...1-0-1-0-1-0.

Yes, I have no idea how it'd work :P If you manage to explain to me, I might be able to make something like this.

[Black Phoenix]

Sine is math sine function, sawtooth is modulus function, square wave is extended sign of sine function (0 if <= 0; 1 if > 0), triangle wave is something like 2 sawtoothes, etc

[Yerocrg]

I think that you could get a square wave by simply attaching a 'round' gate to a 'sine' gate.

[Black Phoenix]

You cant, that won't be square (That will look like steps)

[yaworski]

I think that you could get a square wave by simply attaching a 'round' gate to a 'sine' gate.[/b]

You're wrong. This would generate 3 states for the wave:
if sin(x) <= -0.5 -> -1
if -0.5 < sin(x) <= 0.5 -> 0
if sin(x) > 0.5 -> 1
(assuming the round function is working like in real math ).

You would just quantize the continuous function down to 3 values. But this is not a square wave which (when ideal) should have only 2 values changing with some frequency. You can get a square wave from pulser.

Sin wave should be easy to code since it could just output the value of sin(accumulatedvalue) where accumulatedvalue can be calculated like it is done in accumulator gate.

GateActions["sinwave"] = {
Â*Â*Â*Â*group = "Time",
Â*Â*Â*Â*name = "Sinusoidal Wave",
Â*Â*Â*Â*inputs = { "Rate", "Hold", "Reset" },
Â*Â*Â*Â*timed = true,
Â*Â*Â*Â*output = function(gate, Rate, Hold, Reset)
Â*Â*Â*Â*Â*Â*Â*Â*gate.accumulator = gate.accumulator or {}
Â*Â*Â*Â*Â*Â*Â*Â*local accvalue = GateActions["accumulator"].output(gate.accumulator, Rate, Hold, Reset)
Â*Â*Â*Â*Â*Â*Â*Â*return math.sin(math.rad(accvalue*90))
Â*Â*Â*Â*end,
Â*Â*Â*Â*reset = function(gate)
Â*Â*Â*Â*Â*Â*Â*Â*gate.accumulator = {}
Â*Â*Â*Â*Â*Â*Â*Â*GateActions["accumulator"].reset(gate.accumulator)
Â*Â*Â*Â*end,
Â*Â*Â*Â*label = function(Out, Rate, Hold, Reset)
Â*Â*Â*Â*Â*Â*Â*Â*return "Rate:"..Rate.." Hold:"..Hold.." Reset:"..Reset.." = "..Out
Â*Â*Â*Â*end
}

I put accvalue*90 because I think that without this the change of the value would be too slow, but anyway this can be adjusted by the Rate input. It takes the value from Accumulator gate so the Rate input works like the A input in the Accumulator gate.

I didn't copy the whole code from the Accumulator on purpose, because I like when the code is reusable (there is smaller chance of having error somewhere, and if the error will be found in accumulator code and gets fixed this will automatically fix the sin wave for example).

----edit----

You cant, that won't be square (That will look like steps)[/b]

Hehe you were faster than me .

----edit----

I'll explain why I created the gate.accumulator variable. This is used to simulate the calls that are done by wiremod to the gate's functions. It also stores the state for the simulated Accumulator gate inside my gate's gate variable (so it is persisted through all calls to the output function to the SinWave gate). This can (and should) be done for all gates that store their values through invocations and we want to use them inside our gates (this make the code more readable).

----edit----

Sawtooth

GateActions["sawtoothwave"] = {
Â*Â*Â*Â*group = "Time",
Â*Â*Â*Â*name = "Sawtooth Wave",
Â*Â*Â*Â*inputs = { "Rate", "Hold", "Reset" },
Â*Â*Â*Â*timed = true,
Â*Â*Â*Â*output = function(gate, Rate, Hold, Reset)
Â*Â*Â*Â*Â*Â*Â*Â*gate.accumulator = gate.accumulator or {}
Â*Â*Â*Â*Â*Â*Â*Â*gate.prevValue = gate.prevValue or 0
Â*Â*Â*Â*Â*Â*Â*Â*if gate.prevValue >= 1 then Reset = 1 end
Â*Â*Â*Â*Â*Â*Â*Â*local accvalue = GateActions["accumulator"].output(gate.accumulator, Rate, Hold, Reset)
Â*Â*Â*Â*Â*Â*Â*Â*gate.prevValue = accvalue
Â*Â*Â*Â*Â*Â*Â*Â*return accvalue
Â*Â*Â*Â*end,
Â*Â*Â*Â*reset = function(gate)
Â*Â*Â*Â*Â*Â*Â*Â*gate.accumulator = {}
Â*Â*Â*Â*Â*Â*Â*Â*GateActions["accumulator"].reset(gate.accumulator)
Â*Â*Â*Â*Â*Â*Â*Â*gate.prevValue = 0
Â*Â*Â*Â*end,
Â*Â*Â*Â*label = function(Out, Rate, Hold, Reset)
Â*Â*Â*Â*Â*Â*Â*Â*return "Rate:"..Rate.." Hold:"..Hold.." Reset:"..Reset.." = "..Out
Â*Â*Â*Â*end
}

Triangle

GateActions["trianglewave"] = {
Â*Â*Â*Â*group = "Time",
Â*Â*Â*Â*name = "Triangle Wave",
Â*Â*Â*Â*inputs = { "Rate", "Hold", "Reset" },
Â*Â*Â*Â*timed = true,
Â*Â*Â*Â*output = function(gate, Rate, Hold, Reset)
Â*Â*Â*Â*Â*Â*Â*Â*gate.accumulator = gate.accumulator or {}
Â*Â*Â*Â*Â*Â*Â*Â*gate.prevValue = gate.prevValue or 0
Â*Â*Â*Â*Â*Â*Â*Â*gate.RateDir = gate.RateDir or 1

Â*Â*Â*Â*Â*Â*Â*Â*if (gate.prevValue >= 1 and gate.RateDir == 1) then gate.RateDir = -1 end
Â*Â*Â*Â*Â*Â*Â*Â*if (gate.prevValue <= 0 and gate.RateDir == -1) then gate.RateDir = 1 end

Â*Â*Â*Â*Â*Â*Â*Â*if Reset == 1 then gate.RateDir = 1 end
Â*Â*Â*Â*Â*Â*Â*Â*local accvalue = GateActions["accumulator"].output(gate.accumulator, Rate * gate.RateDir, Hold, Reset)
Â*Â*Â*Â*Â*Â*Â*Â*gate.prevValue = accvalue
Â*Â*Â*Â*Â*Â*Â*Â*return accvalue
Â*Â*Â*Â*end,
Â*Â*Â*Â*reset = function(gate)
Â*Â*Â*Â*Â*Â*Â*Â*gate.accumulator = {}
Â*Â*Â*Â*Â*Â*Â*Â*GateActions["accumulator"].reset(gate.accumulator)
Â*Â*Â*Â*Â*Â*Â*Â*gate.prevValue = 0
Â*Â*Â*Â*Â*Â*Â*Â*gate.RateDir = 1
Â*Â*Â*Â*end,
Â*Â*Â*Â*label = function(Out, Rate, Hold, Reset)
Â*Â*Â*Â*Â*Â*Â*Â*return "Rate:"..Rate.." Hold:"..Hold.." Reset:"..Reset.." = "..Out
Â*Â*Â*Â*end
}

I hope I didn't do any mistake

[Yerocrg]

Actually, I meant using 'sinr' or whatever the one is that outputs between 0 and 1.

[Qjet]

sinr and sind both output -1 to 1

and you would use CEILING on sin to get the square

phoenix is right on basically all counts

except triangle
triangle is abs(2-(X%4))-1
which is 5 gates: modulus, constant, subtract, absolute, decrement.

edit: oops mistake

edit2: i just noticed the 50 lines of code above me were for sawtooth...

don't do the huge if statements and variables use this formula.

edit3: NO WAIT MY FORMULAS TRIANGLE. wtf am i thinking.
sawtooth formula (x%2)-1 and inverted sawtooth 1-(x%2)

[Black Phoenix]

Qjet, shouldn't it be Abs(1-(X%2)) ??

[Qjet]

No waveforms have a range of 1 to -1. and the triangle waveform has a frequency of 4(actually thats the frequency i gave it thats not a true triangle waveform): Here is a list of formula for each wave

Triangle: 1-abs(2-((x*2)%4))
Square: ceil(1-(x%2))
Saw: x%2-1
InvSaw 1-X%2
Sin: sind(x*180) OR sinr(x*pi)
Pulse: floor(x%1)

tell me if i missed any!

edit1: to be honest. I would like to see a waveform gate
it would have 1 input and 6 outputs with these 6 waveforms for each one.